Prior art testing techniques involve operating one or more devices under test (DUTs) over time in a controlled environment. For example, the temperature of the devices under test may be elevated relative to normal operating ranges to increase temperature related stress. Some test environments may utilize a highly capable protocol analyzer, placed between the DUT and the device tester. Upon a failure of the DUT, detailed failure information may be obtained because all communications between the DUT and the device tester may be recorded and analyzed by the protocol analyzer to determine the cause of the failure.
However, it is not commercially feasible to place a highly capable and expensive protocol analyzer between every device under test and its corresponding device tester. For example, a typical single device tester is configured to test many tens, or hundreds of devices under test. The cost of a corresponding number of highly capable protocol analyzers is prohibitive. In addition, it is generally not possible to physically locate and train technicians to use such a high number of highly capable protocol analyzers in a typical environmental chamber. Further, such external protocol analyzer testers are unable to capture data that is not exchanged with a device under test. For example, communications between a test system controller and other functional blocks of a test system are invisible to an external protocol analyzer. Accordingly, conventional mass testing systems generally do not utilize highly capable protocol analyzer testers.
Unfortunately, in accordance with the conventional art, little is known regarding the nature of a failure of a device under test. For example, available failure information may be limited to a time to failure, e.g., an elapsed time until failure. Even less may be known regarding the state of the tester system at the time of failure.